CZ20001214A3 - Preparations exhibiting strong alkalinity and containing hexyl glycoside as hydrotrope - Google Patents

Abstract

The present invention relates to a clear and stable, highly alkaline composition with controlled foaming, containing a high amount of surface active nonionic alkylene oxide adduct and a hexyl glycoside as a hydrotrope. This composition has a very good wetting and cleaning ability and can be used for cleaning of hard surfaces, in a mercerization process and for a cleaning, desizing or scouring process of fibres and fabrics.

Description

HIGH ALKALIC HYDROTROP PRODUCTS containing hexylglycoside as stable, strongly containing non-ionic,

Technical field

The present invention relates to clear and alkaline controlled-foam formulations, high levels of surfactant, alkylene oxide adduct, and hexylglycoside as a hydrotrope. This preparation has very good wetting and cleaning properties and can be used for cleaning hard surfaces, mercerizing and for cleaning, desizing or scrubbing fibers and fabrics.

BACKGROUND OF THE INVENTION

Strongly alkaline formulations, such as concentrates having a high content of alkaline agents, such as alkali hydroxides, alkaline, complexing agents and silicates, and having a pH greater than 11, preferably above 13, are widely used for cleaning hard surfaces, mercerizing, scrubbing, etc. The good wetting ability associated with good cleaning performance is important in the above-mentioned applications which require the presence of a considerable amount of suitable surfactants to reduce the high surface tension caused by the high amount of electrolytes. In these systems it is also important to have controlled foaming. To minimize shipping costs, these concentrates should contain as little water and other solvents as possible. It is also preferred that the concentrates maintain homogeneity during transport and storage.

Since these electrolyte preparations, as complexing agents, it is difficult to dissolve large amounts of surfactants, especially nonionic surfactants. Hydrotropes are often added to increase solubility. the hydrotropes used are ethanol and xylene contains high amounts of alkali and / or alkaline,

Most commonly sodium or cumene sulfonate. Ethanol is quite effective, however, in its

Xylene sulfonate or use may cause explosion. The use of cumene sulfonate is relatively ineffective at higher surfactant levels.

When using a surfactant that is soluble in an alkaline, aqueous solution without the addition of a hydrotrope, there is a problem with a large amount of foam, which requires the addition of a foam depressant.

Previously, alkylglycosides have been used in strongly alkaline formulations. e.g., patent applications EP-B1-589 978, EP-A1-638 685 and US 4,240,921. In addition, alkyl glycosides are well known as active cleaning detergents, cf.

agents commonly used in, for example, WO 97/34971, US 4,627,931 and EP-B1-075 995.

Patent application EP-B1-589 978 discloses the use of C ₈ -C ₁₄ alkyl glycosides as surfactants, desiccants in desizing, bleaching and alkaline scrubbing of natural and / or synthetic flat textile materials, tufts of fibers, while patent application EP-A1-638 685 refers to mercerizing, wetting agents which contain either alone or in combination a C ₄ -C ₁₈ -alkyl glycoside, a C ₄ -C ₁₈ alkylglyconic acid amide and the corresponding sulfonated derivatives. Liquid, strongly alkaline, cleaning concentrates containing alkyl glycosides or alkyl glycidyl ethers and surface active, nonionic, alkylene oxide adducts as described in US Patent 4,240,921 are capable of acting as foam depressants, such as polyoxyethylene / polyoxypropylene block copolymers and protected alcohol ethoxylates. Concentrates contain

a) 10 - 35 wt. alkali metal hydroxide

b) 10-50 wt. a mixture of a first nonionic surfactant which is a polyoxypropylene polyoxyethylene condensate which acts as a foam depressant, and a second nonionic surfactant which is a protected ethoxylated alcohol together with an alkyl glycoside or alkyl glycidyl ether, wherein the weight ratio ranges between · · ····· US 4 alkylglycoside to alkylglycoside or alkylglycidyl ether and the aforementioned first and second nonionic surfactant is from 5: 1 to 10: 1, and

(c) equilibrium water

These concentrates are used to formulate weakly foaming, cleansing compositions which are useful, for example, in the food industry.

However, the above formulation disclosed in Patent 240,921 requires a fairly high ratio of the other nonionic surfactants present in the formulation. Furthermore, it is well known that the inclusion of large amounts of PO in an alkoxylate, such as a Pluronic-type foam depressant, has a negative effect on the biodegradable product. The protected alcohol ethoxylate is normally a mild wetting agent and additionally has a cleaning power. Its presence also increases the need for an additional amount of alkyl glycoside or glycidyl ether.

Therefore, there is a constant demand for strongly alkaline formulations with improved properties.

SUMMARY OF THE INVENTION

It has now been found that strongly alkaline formulations having a pH above 11, preferably at least 13, and most preferably above 13.7, which exhibit excellent cleaning and wetting properties, can be prepared using hexylglycoside having the formula

C ₆ H ₁₃ OG _n (I) wherein the substituent G denotes a monosaccharide moiety and the index n is 1 to 5 as a hydrotrope for a surfactant, nonionic, alkylene oxide adduct which is not soluble in a strongly alkaline preparation and contains a hydrocarbon group or an acyl group o From 8 to 24 carbon atoms and at least one primary hydroxyl group in the alkoxylated portion of the molecule. A suitable adduct has the formula

R (AO) _x (C ₂ H ₄ O) _y H where R is an alkoxy group R'O of 8 to 24 carbon atoms or an RCONR 'group wherein R' is · 9 9 9 9 9 9 9 9 9 0 9 9 9 9 9 9 9 9 9 · · · · · · ·

R '''is hydrogen or - (AO) _x (C 2 H 4 O) _y H, preferably hydrogen, AO is C 2-4 alkyleneoxy, x is from 0 to 5 and y is from 1 to 10 .

The present invention also relates to a composition having a pH above 11 which it comprises

a) 3 - 50% by weight of alkali hydroxide and / or alkaline complexing agent

b) 0.05-30% by weight of a surfactant, nonionic, alkylene oxide adduct having a hydrocarbon group or an acyl group of 8 to 24 carbon atoms and at least one primary hydroxyl group in the alkoxylated part of the molecule,

(c) 0.04-30% by weight of hexylglycoside; and

d) 20-97% by weight of water.

The weight ratio between hexylglucoside and the nonionic surfactant of formula (II) is from 1:10 to 10: 1, preferably from 1:10 to 4: 1.

It should be noted that alkylglucosides have been used in weaker alkaline detergent formulations where other conditions exist. Examples of such formulations can be found in patent applications US 4488981 and EP-B1-136 844 which discloses the use of C ₂ -C 6 alkyl glycosides for reducing the viscosity and preventive phase separation in aqueous, liquid detergents, e.g. in liquid shampoos and soaps and in durable fluids. C ₂ -C ₄ -alkyl glycosides are the most preferred alkyl glycosides because they are most effective in reducing viscosity.

Further, U.S. Patent Application No. 5,525,256 and in the industrial model H 468 describes alkaline and liquid cleaning compositions containing C 8 -C ₂ 5 alkyl glycosides as cleaning agents.

However, none of these references discloses the surprising effects of hexylglycosides in strongly alkaline, cleaning compositions containing at least 3%, preferably at least 20% alkali metal hydroxide and / or alkali fillers, and which which: Have a pH above 11, preferably at least 13, most preferably above 13.7.

Suitable examples of the nonionic surfactants of formula (II) are alkylene oxide adducts obtained by alkoxylation of the alcohol or amide. The substituent group R in formula (II) may be branched or unbranched, saturated or unsaturated, aromatic or aliphatic. Examples of suitable hydrocarbon groups R 'are 2-ethylhexyl, octyl, decyl, cocoalkyl, lauryl, oleyl, rape seed alkyl and tallow alkyl. Particularly preferred hydrocarbon groups R 'are obtained from oxoalcohols, Guerbet alcohols, methyl substituted alcohols having 2-4 groups having the formula -CH (CH ₃ ) - included in the alkyl chain and unbranched alcohols. Other suitable R groups are R''CONH-, aliphatic amido groups, wherein R''CO is preferably derived from aliphatic acids such as 2-ethylhexanoic acid, octanoic acid, decanoic acid, lauric acid, coconut fatty acids, oleic acid, fatty acids obtained from rapeseed and tallow.

The alkaline hydroxide in the formulation is preferably sodium or potassium hydroxide. The alkaline complexing agent may be inorganic or organic. Typical examples of inorganic, complexing agents used in alkaline formulations are the alkali salts of silicates and phosphates such as sodium tripolyphosphate, sodium orthophosphate, sodium pyrophosphate, sodium phosphate and the corresponding potassium salts. Typical preparations of organic, complexing agents, aminopolyphosphine, organic phosphates, such as citrates; aminocarboxylates, are alkali polycarboxylates such as sodium nitrilotriacetate (Na ₃ NTA), sodium ethylenediaminetetraacetate, sodium diethylenetriaminepentacetate, sodium 1,3-propylenediaminetetraacetate, and sodium hydroxyethylethylenediamine triacetate.

• · · φ · φ · φ · · · φ · φ · φ · φ · φ · φ ·

Wetting of the formulation is attributed to the presence of a nonionic surfactant. Hexylglycoside is not a wetting agent per se, but by acting as a hydrotrope for surfactants it increases the wettability of the formulation since otherwise insoluble surfactants are soluble in this way and may exhibit the ability to wet. Concentrates with an unexpectedly high amount of surfactants can be dissolved in a strongly alkaline, aqueous phase and the amount of hydrotrope required to obtain a stable, clear concentrate or formulation is less than in the prior art. This is very surprising since in formulations with other short-chain alkyl glycosides, it is not possible to include as many surfactant, nonionic, alkylene oxide adducts as n-hexylglycoside is present in the formulations. For comparison, the formulations were also made with the short and long alkyl glycosides shown in Example 1.

The formulation of the present invention also exhibits controlled foaming without the need for the addition of a foam depressant that has been required in prior art formulations. All products are environmentally friendly, easily biodegradable and have low toxicity.

The compositions have excellent wetting and cleaning ability and can be advantageously used for alkaline cleaning of rough surfaces, eg vehicle cleaning, mercerization and for cleaning, desizing or scrubbing of fibers and fabrics performed at a pH above 11.

The compositions, when used for cleaning hard surfaces, are commonly diluted with water prior to use, while the compositions may be used as such for mercerization. For cleaning, desizing and scrubbing of fibers and fabrics, the composition may be diluted or not.

In fabric manufacturing, warp yarns are exposed to a huge load and must therefore be provided with a protective layer, a sizing agent that adheres to the fiber and becomes an abrasion-resistant elastic layer. Two major groups of the sizing agent are macromolecules, natural substances and derivatives thereof, e.g. starches, synthetic polymers, e.g.

and carboxymethylcellulose and polyvinyl compounds.

The sizing agent, if the fabric has been knitted, must be fully removable, as this has a harmful effect in the later final process. The desizing process may be enzymatic or oxidative and is normally completed in additional alkaline scrubbing and bleaching cycles where the initially water-insoluble, starch degradation products and residual particles are degraded partially hydrolytically and partially oxidatively and removed.

During scrubbing, the intramolecular and intermolecular hydrogen bonds of cellulose are broken and the polar hydroxyl groups of the polysaccharides are solvated. Transport of undesirable substances from the inside to the outside occurs. In an alkaline environment, hydrolytic decomposition of various plant parts takes place and fats and waxes are also hydrolyzed. When NaOH is used, the alkaline concentration is about 4-6%.

In the scrubbing process, the adjuvants need to effectively moisturize, emulsify and disperse water-insoluble undesirable impurities, form a complex with heavy metal ions, and protect against fiber damage by atmospheric oxygen. Here alkali-resistant detergents form an important group of additives. It is also very important that an adequate amount of humectant / detergent is insoluble in an alkaline, aqueous solution that often requires the addition of a hydrotrope. The same applies, to a greater extent, to mercerisation, which is principally carried out to improve the dyeability of cotton. The process involves treating cotton under tension with a 20-26% sodium hydroxide solution at 15-25 ° C for 25 40s. This treatment destroys the spiral form of cellulose, thereby improving access to water and, consequently, water-based dye. In addition to good wetting and base resistance, it is also important that 0000000 00 0 0 0 0 0 0 0 0 00 00 00 00 that the additives do not cause foaming, as this could interfere with the rapid wetting required in the mercerization baths.

Examples

The present invention is further illustrated by the following examples.

Example 1

This example illustrates various amounts of alkylglucoside hydrotropes, RO (G) _n /, which are required to obtain clear solutions of 5% nonionic surfactant in a solution containing 10, 20, 30 and 40% NaOH. The nonionic surfactant used was a C 8 -C 14 alcohol with a linearity above 80% which was ethoxylated with 4 molar ethylene oxide per 1 mol of alcohol in the presence of a narrow span catalyst. The glucosides tested were laboratory samples, except butylglucoside, which is commercially available from SEPPIC. The degree of polymerization is between 1.4 and 1.6 with a slightly higher amount of glucose for longer alkyl chains.

Method:

5% of the nonionic surfactant is added to an aqueous solution with different amounts of sodium hydroxide. Test hydrotropes are added dropwise at room temperature to an aqueous mixture of nonionic surfactant and sodium hydroxide in an amount sufficient to obtain a clear solution.

NaOH (%) n- butyl- glucose- id «✓ (%) Isoamy 1- glucose- id (%) n- hexyl- glucosicl (%) Exxal 7 4 Glukosicl (%) 2-ethyl- hexylgluko · sid (%) 40 7.5 9.4 very viscous

· · · · · · · · · · · «« *

4 ·· 4 444 4 · · «4 4 ··· 4 · 4 4444 4 4 · · · 4 4 44 4 4 * 44 · * 4 4 * 4 44 44

volatile 20 May - - 3.5 4.7 8.1 10 13, 8 7.6 3.3 3, 6 4.6

- the solution obtained is not clear ¹ glucoside consisting of a methyl-substituted alcohol containing groups of the formula -CH (CH3) - contained in the alkyl chain

The results clearly show that the solubilizing effect of hexylglycoside is better than the solubilizing effect of the alkylglucosides used for comparison.

Example 2

The same procedure as in Example 1 was used to compare the efficacy of n-hexylglycoside to other types of hydrotropes.

Hydrotrop in the preparation Amount hydrotropes in 10% NaOH (%) Amount hydrotropes in 20% NaOH (%) Amount hydrotropes in 30% NaOH (%) Amount hydrotropes in 40% NaOH (%) n-Hexylglucoside 3.3 3.5 4.0 7.5 Oktyliminodi- propionate 1.7 4,5 Cumensulfonate 4.8 - - -

- the solution obtained was not clear

Tests have shown unexpectedly good solubilizing ability of nhexylglucosides, especially at higher alkalinity.

Example 3

The surface tension was measured according to du Nouy (DIN 53914). The first three solutions contained 5% of the same nonionic surfactant as used in Examples 1 and 2. The same hydrotropes as in Example 2 were used in different amounts.

For a solution containing only n-hexylglucoside, the amount was (5 + x)%, where x is the amount used in Examples 1 and 2.

9

9

99 • 99 9 9 9

9 1 9 9 9 1 1 1 1 9 1 · · »» »» »» »»

11 9 11 9 9 9

9 9 9 11 11 19

Hydrotrop Surface tension Surface tension Surface tension Surface tension in the preparation in 10% NaOH (mN / m) in 20% NaOH (mN / m) in 30% NaOH (mN / m) in 40% NaOH (mN / m) n-Hexylglucoside 27.9 30.0 29.3 40.8 Oktyliminodi- propionate 27.8 29.6 Cumensulfonate 29.1 - - - n-Hexylglucoside and none surfactant 31.9 33.5 37.1 55.9 Without adding hydrotrope or surfactant 64.6 68.4 74.2 85.1

- the solution obtained was not clear and no surface tension was measured for these preparations

Example 4

To measure the wetting ability of strongly alkaline formulations containing n-hexylglucoside and non-ionic surfactants, a modified Drave test was used to compare to decylglucoside alone. In this test, the descent time (in seconds) for the specified cotton yarn in about 0.1% surfactant solution is measured. In this example, the concentrations for hexylglucoside and nonionic surfactant are used, which are shown in the table below.

Components % by weight components % NaOH in Descent Time (s) n-Hexylglucoside C ₉ -C 11 -alcohol + 4 EO 0.04 0.05 25 141 n-Hexylglucoside 0.05 25 > 2000 Decylglucoside 0.05 25 472

* · · ·

• 9 ·

9 9 9

4 9999

9 9

9

9 9 9 9 9 9

9 9999 9 9 9 4 * • · · · · ·

9 99 99

n-Hexylglucoside 2-ethylhexanol + 4 EO 0.08 0.10 6 7 n-Hexylglucoside 0.10 6 > 2000 Decylglucoside 0.10 6 23

For comparison, decylglucoside was used since it is an example of a nonionic surfactant that is soluble in an alkaline, aqueous solution in the absence of any hydrotrope.

The data in the table shows that n-hexylglucoside does not have its own wettability.

Example 5

The wetting angle was measured with surfactant solutions at the concentrations shown in the table below, compared to the hydrophobic polymeric substance (Parafilm). The angle was measured with a goniometer for 1 min. after fluid application. Decylglucoside was used for comparison.

Component % by weight components % NaOH Wetting angle (s) n-Hexylglucoside C9-C11-alcohol + 4 EO 0.08 0.10 25 41 n-Hexylglucoside 2-ethylhexanol + 4 EO 0.08 0.10 25 42 Decylglucoside 0.10 25 96

Example 6

The foam is measured as foam (in mm) formed in a 500 ml graduated cylinder with an internal diameter of 49 mm from a 200 ml surfactant solution, where the graduated cylinder is rotated 40x per minute. The test is performed at room temperature and the foam height is recorded at time 0 and after 1 and 5 minutes. Decylglucoside was used for comparison.

and

φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ · · · φ φ φ

Component % by weight components % NaOH Foam height (mm) at 0 min Foam height (mm) after 1 min after 5 min n-Hexylglucoside C ₉ -C 11 -alcohol + 4 EO 0.08 0.10 25 4 2 0 n-Hexylglucoside 2-ethylhexanol + 4 EO 0.08 0.10 25 5 4 0 Decylglucoside 0.10 25 88 85 83

Example 7

The following two formulations were prepared to determine the cleaning performance of the formulations using hexylglucoside as the hydrotrope compared to the formulation using sodium cumene sulfonate as the hydrotrope.

Komponento Formulation I % by weight of the component Formulation II % by weight of the component C ₉ -C ₁₁ -alcohol + 4 EO 5 5 NaOH 10 10 n-Hexylglucoside 6 ^1} - Sodium cumenesulfonate - 12 ^υ Water balance balance

’’ This amount was needed to obtain a clear solution.

The cleaning performance of the formulations shown in the table above was determined using the following cleaning test: A mixture of oil and soot obtained from diesel engines (Diesel) was spread over white surfaces. Test solutions (25 mL) were poured onto the top of the spread mixture and waited for a few minutes. The surfaces were then washed with a strong stream of water. All solutions and water were tempered at a temperature of about 15-20 ° C. Both test solutions were placed on the same plate.

Surface reflectance was measured before and after cleaning with a Minolta Chromá Meter CR-200 reflectometer.

i »4 • 4

4 4 ·

• 4 4 4

4 4 4

4 4 4 ·

4 4 4 4

44 44

The test was performed with concentrates and solutions diluted to 1: 3 with water. The swept impurity was calculated on a computer program integrated in the meter, giving about 85% of the eluted impurity for Formulation I of the invention and about 44% of the eluted impurity for Reference Formulation II. For solutions diluted 1: 3, the corresponding amounts were 68% and 21% respectively.

It has also been found, when using n-hexylglucoside as the hydrotrope, that the hydrophobic impurity, which is emulsified in the purification process, can be readily separable from the waste water after dilution with water. This is a very important advantage, as there is an increasing demand for lower lubricant content in wastewater.

Example 8

The table below shows some examples of the amount of nhexylglucoside required to obtain a clear solution in water with different types and amounts of nonionic surfactants with different amounts of Na ₃ NTA added.

Nonionic surfactant % by weight surfactant % by weight Na ₃ NTA % by weight hexylglucoside n- C9-C11-alcohol + 6 EO 20 May 20 May 19.2 C9-C11-alcohol + 6 EO 10 30 13.8 C 12 -C 14 -alcohol + 6 EO 20 May 20 May 16.5 C 12 -C 14 -alcohol + 6 EO 10 30 14.1 C9-C11-alcohol + 4 EO 5 35 7.5 C9-C11-alcohol + 4 EO 10 35 12.8 Monoethanolamid oleic acid + 4 EO 10 30 10.6 Monoethanolamid coconut acid + 2 EO 30 10 11.9

·· · 99 «·· ··

Claims (10)

PATENT CLAIMS Use of a hexylglycoside as a hydrotrope having the formula C ₆ H ₃ OG _n (I), wherein the substituent G is a monosaccharide moiety and the index n is 1 to 5, in a strongly alkaline formulation having a pH above 11 containing a surfactant, nonionic, alkylene oxide an adduct that is insoluble in a strongly alkaline preparation and contains a hydrocarbon group or an acyl group of 8 to 24 carbon atoms and at least one primary hydroxyl group in the alkoxylated portion of the molecule. Use according to claim 1, wherein the adduct has the formula R (AO) _x (C ₂ H ₄ O) _y H (II) wherein R is an alkoxy group R 10 of 8 to 24 carbon atoms or RCONRR- wherein R is a hydrocarbon group having 7 to 23 atoms atoms, R '' · 'represents a hydrogen atom or a group - (AO) _x (C ₂ H ₄ O) _y H, AO is an alkyleneoxy group with 2-4 carbon atoms, x is a number from 0 to 5 and y is number 1 to 10. Use according to claim 1 or 2, wherein the alkaline preparation has a pH value above 13. Use according to claim 1, 2 or 3, wherein the glycoside is nhexyl glycoside. 5. An aqueous, alkaline preparation having a pH value above 11, comprising: i · Φ · Φ · · · · · · · · · φφφφφφφ φ · · · · ·φφ · · · φφφφ ·φ · φφφφφφφφφφφφφφφφφφφ a) 3-50 wt. an alkali hydroxide and / or an alkaline complexing agent b) 0.05 - 30 wt. a surface-active, non-ionic, alkylene oxide adduct having a hydrocarbon group or an acyl group of 8 to 24 carbon atoms and at least one primary hydroxyl group in the alkoxylated portion of the molecule, c) 0.04 - 30 wt. hexylglycoside and d) 20-97 wt. water. The composition of claim 5, wherein the nonionic surfactant is an alkoxylate having the formula R (AO) _x (C ₂ H ₄ O) _y H (II) wherein R is an alkoxy group R'O- having 8 to 24 carbon atoms or a group R 6 CONRR- wherein R 'is a hydrocarbon group of 7 up to 23 carbon atoms, R 'is hydrogen or - (AO) _x (C ₂ H ₄ O) _y H, AO is C 2-4 alkyleneoxy, x is 0-5 and y is number 1 to 10. Composition according to claims 5 to 6, characterized in that the weight ratio between c) and b) is from 1:10 to 4: 1. Composition according to claims 5 to 7, characterized in that its pH value is above 13. Composition according to Claims 5 to 8, characterized in that the hexylglycoside is n-hexylglycoside. Use of an alkaline preparation according to claims 5 to 9 in mercerization. I • · · · t · V l V I V clean 12. cleaning Use of an alkaline preparation according to claims 5 to 9 for hard surfaces. Use of an alkaline preparation according to claims 5 to 9 in desiccating or scouring fibers and fabrics.